@misc{indiciae2f13cadd9ccd,
  title = {Individual problem rating: a proposed scale.},
  author = {D F Gillespie and J R Seaberg},
  doi = {10.1007/bf00820959},
  url = {https://pubmed.ncbi.nlm.nih.gov/614778/},
  note = {Source identifier: 614778}
}